| Objective: ||Develop a concept and design for a low-cost, high-sensitivity optical sensor to provide remote sensing of the ionosphere and/or upper atmosphere from space platforms.
|| Description: ||The ionosphere and upper atmosphere have considerable impact on a variety of DoD missions, including communications, navigation, surveillance, reconnaissance and space object identification and tracking. Efforts to understand and forecast conditions in the upper atmosphere and ionosphere have been hampered by the sparsity of data from routine measurements and observations, which are often single points or limited to specific ground stations. As demonstrated by the Global Ultraviolet Imager (GUVI) and other recent on-orbit optical instruments, optical measurements from space platforms have the potential to provide large quantities of important measurements and revolutionize space weather specification and forecast activities. This is especially true for sensors that can be made small enough (in terms of size, power, weight and telemetry requirements) and inexpensive enough to allow their inclusion as secondary payloads on a variety of space platforms or to be employed on microsatellites, while retaining the sensitivity required to accurately measure the very low photon fluxes from airglow or other emission sources.
Innovative concepts for space-based optical remote sensing of the ionosphere and upper atmosphere are desired, especially those that can provide two dimensional spatial coverage (horizontal or vertical) with minimal use of moving parts. Measurement parameters of interest include ionospheric plasma density, plasma density profiles, and thermospheric composition, density, and temperature. Concepts employing emissions ranging from ultraviolet (UV) through visible and infrared wavelengths will be considered, although it is expected that individual proposals will focus on only a subset of the parameters of interest and a specific spectral region. Potential space platforms include polar orbiting satellites such as DMSP/NPOES, and equatorial orbiters such as C/NOFS follow-on missions, where cross-track optical data could potentially image both anomaly crests and all plasma bubbles on every orbit.
Successful proposers will demonstrate an understanding of what emission lines or bands are available, what information they carry, what intensities can realistically be expected, and what the limiting factors on the observation would be (daylight, twilight, moonlight, ground illumination, total photon flux, spatial gradients, etc.). Successful proposals are also expected to evidence thorough understanding of the trade-offs between spacecraft motion, integration time, spatial resolution, line-of-sight integration effects, and signal-to-noise ratios, as well as design features necessary for successful operation in the space environment.
|| ||PHASE I: Develop a concept for a low-cost, low-power, lightweight, high-sensitivity optical instrument for remote sensing of the ionosphere and/or upper atmosphere from orbit, including a detailed formulation relating the measured parameter(s) to the target ionospheric or upper atmospheric quantities.
|| || ||PHASE II: Develop a detailed design for the instrument concept produced in Phase I. Produce and deliver a realistic software simulation of the instrument and a functioning engineering prototype from the design and perform ground testing to compare prototype performance with the simulation.
|| ||DUAL USE COMMERCIALIZATION: Military application: A successful instrument could be expected to find broad application as a secondary payload on a wide variety of DoD spacecraft, including a C/NOFS follow-on mission. Commercial application: A wide range of civilian space weather applications is possible, as expensive research instruments are followed up by less expensive operational sensors on future missions including micro satellites.
|| References: ||
1. Paxton, Larry J., Daniel Morrison, Douglas J. Strickland, M. Geoff McHarg, Yongliang Zhang, Brian Wolven, Hyosub Kil, Geoff Crowley, Andrew B. Christensen and Ching-I Meng, "The use of far ultraviolet remote sensing to monitor space weather," Advances in Space Research, Volume 31, Issue 4, p. 813-818, 2003.
2. Christensen, A. B., L. J. Paxton, S. Avery, J. Craven, G. Crowley, D. C. Humm, H. Kil, R. R. Meier, C. I. Meng, D. Morrison, B. S. Ogorzalek, P. Straus, D. J. Strickland, R. M. Swenson, R. L. Walterscheid, B. Wolven and Y. Zhang, "Initial observations with the Global Ultraviolet Imager (GUVI) in the NASA TIMED satellite mission," Journal of Geophysical Research, Volume 108, Issue A12, pp. SIA 16-1, CiteID 1451, DOI 10.1029/2003JA009918, 2003.
3. Dymond, K. F., J. B. Nee and R. J. Thomas, "The Tiny Ionospheric Photometer: An Instrument for Measuring Ionospheric Gradients for the COSMIC Constellation," Terrestrial, Atmospheric and Oceanic Sciences, Vol. 11, pp. 273-290, 2000.
|Keywords: ||airglow, microsatellites, remote sensing, ionosphere, thermosphere, optical techniques, miniaturization|